The DOIs of these papers are fake. DOIs normally start with "10," not "16," as in this screenshot. This journal is a hijacked one, i.e., a cloned version (https://novyimir.net/) of the authentic journal. You can find the full list of hijacked journals at the Retraction Watch Hijacked Journal Checker (https://retractionwatch.com/the-retraction-watch-hijacked-journal-checker/).